UA 777 then AA 3974 at O'Hare
Tampa → Chicago → Harrisburg
Timetable, Chicago time
09:23UA 777 from Tampa at the gate
08:27AA 3974 to Harrisburg leaves the gate
23 h 04 apart on the timetable, overnight
AA 3974 leaves 23 h 04 after UA 777 arrives on the timetable: more than half a day, so not a connection we count.